Mechanical time fuse



Sept'.` 19, 1933.'

H. JUNGHANS 1,927,746

MECHANICAL TIME lFUSE Filed July 30.V 1951 2 Sheets-Sheet 1 Sept. 19,1933 H. JUNGHANS MECHANICAL TIME FUSE Filed July 50, 1931 2 Sheets-Sheet2 Patented sept. 19, 1933 1,927,746 MECHANICALTIME FUSE Helmut Junghans,Schramberg, Germany,

signor to Societa onima Arturo Junghans Fabrica DOrologeria, Venice,Italy Applition July ao, 1931, serial No. 554,102, and in Germany August15, 1930 2Claims.

The present invention relates to mechanical time fuses and moreparticularly to the igniting or' detonating mechanism thereof.

As compared with the igniting mechanism 5 hitherto designed or suggestedin connection with time fuses and wherein ignition is effected by meansof a spring or spring-controlled striker which must b e kept in stressedcondition during storage, the chief object of the present invention isto dispense with such springs, in order to thereby overcome certaindisadvantages and objections concomitant with said springs. Accordingly,in my improved time fuse, ignition takes place merely by the action ofcentrifugal force and without the use of a spring-controlled striker,preferably a percussion cap or primer as usually provided in the fuse,being caused to strike upon a stationary detonating pin after theexpiration of the time interval for which the fuse has been set.

Apart from the constructional simplicity of time fuses made inaccordance with the present invention the main advantage of the latter,however, resides in the fact that spring-controlled striking bolts areentirely dispensed with and the disadvantages inherent in andvespecially due to the permanently tensioned condition of the springsduring storage andtransportation resulting in loss of strength oreven'fracture, are

entirely avoided.

In a fuse constructed in accordance with the present invention thedetonating cap is accommodated in a radially movable slide which islocked normally or while in condition of rest,

duringstorage and transportation, and adapted to be unlocked by means ofa recoiling or iiyngback bolt and to be released bythe agency ofthesetting disk for the ignitingpurpose. In order to prevent the projectilefrom explosion within thebarrel of the ordnance, I provide asupplemental safety device in the form of a cam adapted to project intothe path of the slide and to be rotated by the work of the fuse so as to5 clear the said path of the slide, a certain time after the projectilehas left the ordnance.

The unlocking and releasing of the slide by means of the flying-back orrecoiling bolt and the setting disk is accomplished or initiated by apawl mounted on a pivot so as to be capable of turning thereabout andadapted to catch into a recess or dwell provided in the slide, the saidpawl being preferably connected with the flyingback or recoiling bolt bymeans of intermediate members whereof one is disengaged from therecoiling bolt upon firing of the shot, and adapted to engage, due tocentrifugal action, in a recess of the setting disk so as to therebycause the pawl to disengage from the dwell of the slide.

I will now proceed to describe my invention more in detail in connectionwith the embodiment thereof, illustrated on the accompanying drawings,it being intended andunderstood that the invention is illustrated by butnot limited to the embodiment thereof so illustrated and described.

In the accompanying drawings forming a part of this specification andshowing, for purposes of exempliiication, a preferred form and manner inwhich the invention may be embodied, but without limiting the claims tosuch illustrative instance:

Figure 1 is a sectional view illustrating a part including theclock-work, of the regulating drive mechanism which is adapted at thesame time to actuate the means for preventing premature detonationwithin the barrel of the ordnance; Figure 2 is a similar sectional viewshowing the igniting device viewed from the timing disk; Figure 3 is aview in 'top plan of the setting disk; Figure 4 is a view in sectiontaken on the line IV-IV in Figures 1 and 2, showing in plan view, boththe drive mechanism and the disengaging device; and Figure 5 is a Viewin top plan of the lowermost or innermost plate on which the ignitingdevice is mounted.

In the preferred embodiment shown the detonating cap f is accommodatedin a slide g adapted to move radially with relation to the axis of theprojectile and provided with a lateral recess, catch or dwell for a pawlh to engage therein, the back of the pawl being adapted to iit inarecess of the shaft i. Keyed to the latter is a short lever i1 ofconventional con struction adapted to permanently engage or rest 9 onashaft k as usual in fuses of the type to which my invention belongs. Theupper or outer end of the shaft k is equipped with a dropping lever kl,as usual, -and a locking pin k2 adapted to engage and lie in contactwith the 100 dying-back or recoiling bolt l, so that, normally or duringstorage and Itransportation, the said dropping or setting lever k1 willnot be in contact with the setting disk m and, therefore, -will not becapable of dropping into the peripheral 105 recess m1 of the latter, seeFigure 3.

The clock-Work further is adapted, by means of suitable transmissionmembers, to rotate a shaft o integrally formed or otherwise rigidlyconnected with a cam o1 adapted to protrude 110 in the path of the,slide g and remain therein during a certain predetermined interval oftime after the firing of the shot, so that the slide will be locked andcannot move until or before the said interval of time has elapsed. Forthe rotation of the cam is calculated or controlled in such manner thatupon ring and simultaneous operation or starting of the clock work, thecam does not and cannot move out of the path of the slide before oruntil the projectile has left the ordnance and is far od lthe muzzlethereof. A small at spring p serves as a means for retaining the slidecarrying the detonation cap f immovable in normal position duringtransportation.

The operation of the improved arrangement is as follows:-

Upon ring, the recoiling bolt 1 will ily back (or downwards in Figure 2)due to inertia so as to release the pin la and thereby permit the leverk1 to engage the periphery of the setting disk m due to the centrifugalaction of a counter-weight attached to the one arm of the lever. As theclock work now is running the bent end or nose o'f the other armof thelever k1 willdroplinto the peripheral recess m1 ofthe setting disk mafter the expiration of the time for which the disk has been set, andconsequently the shaft Ic will be turned for an angle sumcient to allowthe lever i1 to move and engage .in a recess provided in the shaft Ic,mainly due to centrifugal action.

The shaft, moving in the direction of the arrow, shown in Figure 5,releases the pawl h which in turn disengages from the dwell of the slideg, so Athat the latter will y outwards due to centrifugal action and thestationary pin or needle n will strike upon the fulminate at the bottomof the cap f. This, however, cannot occur except when the shaft o hasbeen turned in the direction of the arrow shown in Figure 5, through anangle sulcient to move the cam o1 out of the path of the slide. Thepinion keyed to the shaft o, see Figure 4, and meshing,

with the toothed wheel of the next following shaft of the gearing, is inthe form of a toothed segment.V only and as soon as the last tooth ofthis pinion or segment disengages from the said toothed wheel. whichcannot occur except when the projectile has left the ordnance and is aconsiderable distance awayl from the muzzle thereof, as will be readilyunderstood from the description of the operation, the cam ol will Fri.

tion prior to the described rotation of the shaft' o and cam o1, theedge of the front or outer end of the slide g will abut against the camo1, so that the slide cannot ily outwards, thereby preventing thedetonating cap from being struck by the needle n.

Moreover, safety against premature bursting of the proiectilewithin thebarrel of the ordnance is further warranted by the fact that in case ofsuch accidents the shaft o will be braked by the frictional contactbetween the slide g andthe cam ol to such a degree that the entiremechanism will be stopped and inoperative. The fuse will be blind insuch a case.

I have herein described and shown one preferred and practical embodimentof my present improvements, but it will be apparent that the inventionis susceptible of embodiment in other alternative forms and changes inthe arrangement, commotion and combination of the several parts shownand described. For instance I would have it understood that while in theembodiment described and illustrated the primer or detonating cap ismoved to strike upon a stationary pin or needle, the parts may bearranged suchwise that a movable striking bolt or pin will be caused tostrike vand penetrate into a primer or detonating cap, when theprojectile is red oil, without thereby departing from the spirit of theinvention. Y

What I claim is:

1. A mechanical time fuse for projectiles wherein ignition is eiectedsolely by centrifugal action, comprising a movable body having adetonating member, and adapted to be moved under centrifugal actionafter the expiration of the time interval for which the fuse has beenset, said movable body being shaped to forma radially displaceableslide, means normally locking said slide during storage andtransportation, a recoil bolt and a setting disk adapted to unlock andrelease said slide upon ring, after the expiration of the said set timeinterval, and means 1 for preventing premature ignition after ring theprojectile, whilethe projectile is stillwithin the barrel of the gun,said means comprising a cam -projecting normally into the path of thesaid slide, and mechanism to move the same. to release the slidecompletely, prior to the time that the same is released by the settingdisc, but subsequent to the instant at which the projectile leavesthebarrel of the gun.

2. A mechanical time fuse for projectiles wherein ignition is effectedsolely by centrifugal action, comprising a movable body having adetonating member, and adapted to be moved under centrifugal actionafter the expiration of the time interval for which the fuse/has beenset,

said movable body being shaped to form a radially displaceable slide,means normally locking said slide duringstorage and transportation, arecoil bolt and a setting disk adapted to unlockA and release said slideupon ring, after the expiration of the said set time interval, a' pawl,means intermediate between and connecting the pawl and the recoil bolt,to engage and lock the said slide, one of said intermediate means beingarranged to be released from the recoil bolt upon 135 ring, and arrangedto subsequently engage the periphery of the setting disk due solely tocentrifugal action, said disk having a recess in its margin, whereby thesaid means will nally engage in said recess and thereby cause the pawlto becomedisengaged from the slide.

HELMUT JUNGHANS.

